Re: gettimeofday nanoseconds patch (makes it possible for theposix-timer functions to return higher accuracy)

[Christoph Lameter]

On Thu, 15 Jul 2004, George Anzinger wrote:

> As to accuracy, the more "accurate" way is to change get_offset to return
> nanoseconds.  This way there is only one round off (by the divide) instead of
> two (the get_offset and the divide).  I ran into this problem in the latest HRT
> patch.  One of my tests is to do a gettimeofday and a clock_gettime and make
> sure there is no "backward" stuff happening.  Test failed by 1 micro second
> "some" of the time because of this double round off.

Well yes this is what the interpolator etc does on IA64.
time_interpolator_get_offset returns nanoseconds. I have done
tests to insure that no backward stuff happens. Tests were done
with the mentioned patch and clock_gettime was returning nanosecond
accuracy.


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